The Silent Auditorium Bandana skull requires you to not kill any Setinals. Heroic/Legendary makes this extremely difficult. Here's a fun detour through that room. : r/halo
Halo Infinite skull locations: Find all 12 with our skulls map - Polygon
Halo Infinite skull locations: Find all 12 with our skulls map - Polygon
Halo Infinite Bandana Skull Legendary - YouTube
Halo Infinite Where To Find The Bandana Skull On The Silent Auditorium - YouTube